In the lead up to the U.S. elections, two documentaries, one conservative the other liberal, are trying to discredit the presidential candidate of the opposite camp. Dinesh D' Souza's "Obama's America 2016" criticizes President Obama, a Democrat, as un-American, while the liberal mockumentary "Janeane From Des Moines" pokes fun at the Republicans on issues such as health care, gay marriage and the economy. These films attempt to sway voters. But can they?